Excellent news everyone! Last month we launched SSH tunnels for Browserling. SSH tunnels allow you to tunnel your localhost or local network straight through to Browserling, which means you can do cross-browser testing from your internal network!

SSH tunnels is the first major feature that differentiates the paid plans from the free plans. In free plans you get 5 minutes of Browserling for free and no tunnels. With a paid plan you get tunnels and unlimited time.

Here is a brief technical overview of how the tunnels work.

We run the tunnel.browserling.com openssh server. The first time you use tunnels, you'll be asked to choose your ssh password and a new no-login Unix user will be created for you on the tunnel.browserling.com server. The server has ports 50000-60000 open for tunneling but they are firewalled with iptables. When you click the "open tunnel" button in the Browserling UI, the tunnel server generates a random port in this range and opens it up with iptables but only for your Browserling session. For example, it may open up tunnel.browserling.com:55555. Then it generates the ssh command for opening a reverse ssh tunnel for you. For example, if you're tunneling localhost:80 then the command that will be generated will be ssh -N -R 55555:localhost:80 your_login@tunnel.browserling.com. Now you can just copy and paste this command to the terminal, you'll get prompted for your password, and you're done. The tunnel between Browserling and your localhost:80 has been opened. Now if you visit http://tunnel.browserling.com:55555 inside of Browserling, the connection will go through the tunnel and you'll really be accessing localhost:80!

If you're on Windows, you can also easily tunnel your localhost or local network with the plink.exe program from PuTTY. It turns out that the command line arguments for plink.exe are exactly the same as for ssh. In the example above it would be plink.exe -N -R 55555:localhost:80 your_login@tunnel.browserling.com. Really cool!

We are huge fans of open-source at Browserling and we have open-sourced 40 node.js modules! I'll do a blog post about that soon. Then we are releasing Testling the next two weeks, which is an automated web testing framework for Browserling, and I am going to announce it here also. And we're adding a ton more web browsers to Browserling in the upcoming week!

Browserling is an interactive cross-browser testing site that allows you to use Internet Explorer, Firefox, Chrome, Opera and Safari from your browser. We built this amazing technology that brings virtual machines to the web and we built Browserling on top of it!